<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>京东css三角制作</title>
    <style>
        .box1{
            position: relative;
            width: 100px;
            height: 200px;
            background-color: pink;
        }
        .box2{
            position: absolute;
            right: -19px;
            top: 8px;
            width: 0;
            height: 0;
            border: 10px solid transparent;
            border-left-color:lightblue ;
        }

    </style>
</head>
<body>
    <div class="box1">
        <div class="box2"></div>

    </div>
    <div class="box3"></div>
</body>
</html>